The disclosure of Japanese Patent Application No. 2000-401608 filed on Dec. 28, 2000, including the specification, drawings and abstract, is incorporated herein by reference in its entirety.
1. Field of Invention
The present invention relates to a system and a method for controlling a vehicle-occupant protecting apparatus such that the vehicle-occupant protecting apparatus is operated upon detection of a rollover motion of an automotive vehicle.
2. Description of Related Art
It is known to provide a control system for controlling a vehicle-occupant protecting apparatus such that at least one airbag and/or at least one seat-belt pre-tensioner is/are operated upon collision of an automotive vehicle, to protect occupants of the vehicle. JP-A-2000-503278 discloses an example of such a control apparatus, which is arranged to selectively operate various airbags at suitable time intervals, depending upon the state of the vehicle collision.
However, the known technique described above suffers from a drawback that a rollover motion of the vehicle is not sufficiently taken into consideration.
It is one object of the present invention to provide a control system and a control method for a vehicle-occupant protecting apparatus, which permit the vehicle-occupant protecting apparatus to be operated adequately upon detection of a rollover motion of an automotive vehicle.
The above and/or other objects may be achieved according to one aspect of the present invention, which provides a control system for controlling a vehicle-occupant protecting apparatus including at least two vehicle-occupant protecting devices which are disposed on respective right and left sides of an automotive vehicle, including: a controller that (i) determines whether the vehicle has a rollover motion, on the basis of at least one physical quantity indicative of a running condition of the vehicle; and (ii) upon determining that the vehicle has the rollover motion, operates at least one of the vehicle-occupant protecting devices located on a rolling side of the vehicle.
In the present control system, the controller preferably further is operable after an operation of the above-indicated at least one rolling-side vehicle-occupant protecting device, to operate at least one of the non-rolling-side vehicle-occupant protecting devices. For example, the controller may, after determining that the vehicle has the rollover motion, determine whether the rollover motion of the vehicle is expected to develop into a serious rollover motion. In this case, the controller is adapted to operate the above-indicated at least one non-rolling-side vehicle-occupant protecting device after the rolling-side vehicle-occupant protecting device has been operated.
The above and/or other objects may also be achieved according to another aspect of the present invention, which provides a method of controlling a vehicle-occupant protecting apparatus including at least two vehicle-occupant protecting devices which are disposed on respective right and left sides of an automotive vehicle, including the steps of: detecting a lateral acceleration value of the vehicle; detecting a roll rate of the vehicle; calculating a roll angle of the vehicle; determining whether a running state of the vehicle represented by the roll angle and roll rate of the vehicle has fallen within a predetermined rollover region (A) defined by threshold lines representing a relationship between the roll angle and rate of the vehicle; determining whether a running state of the vehicle represented by the detected lateral acceleration value and roll rate of the vehicle has fallen within a predetermined rollover region (B) defined by threshold lines representing a relationship between the lateral acceleration value and roll rate of the vehicle; determining that a rollover motion of the vehicle has taken place, when the running state represented by the roll angle and rate has fallen within the predetermined rollover region (A) or when the running state by the detected lateral acceleration value and roll rate has fallen within the predetermined rollover region (B); and operating at least one of the vehicle-occupant protecting devices located on a rolling side of the vehicle.
The control system and method for controlling the vehicle-occupant protecting apparatus as described above are arranged such that upon determination that the vehicle has the rollover motion, only the rolling-side vehicle-occupant protecting device or devices located on the rolling side of the vehicle can be operated, while the non-rolling-side vehicle-occupant protecting device or devices located on the non-rolling side of the vehicle is/are not operated. Accordingly, the present arrangement prevents unnecessary operation of the non-rolling-side vehicle-occupant device or device, and consequently saves the repairing cost of the vehicle.
Further, the present arrangement permits operation of the non-rolling-side vehicle-occupant protecting device or devices at an adequate timing. In some cases, the present arrangement permits simultaneous operation of the rolling side and the non-rolling side vehicle-occupant protecting devices.